Carpal Tunnel Syndrome

CONDITION

The carpal tunnel is a narrow passageway of bones and tissues just below the wrist on the palm side of your hand. Tendons and the median nerve pass through the carpal tunnel. The median nerve controls feeling to the palm side and tips of your thumb, index and middle fingers, and to the skin that covers about half of your palm (Figure 1). It gives your fingers strength when they bend and make a fist. Carpal tunnel syndrome occurs when the median nerve is squeezed or pinched, which can result in pain, tingling, weakness and/or numbness in your hand.

Figure 1.

CAUSES

Inflammation, injury or anything that compresses the median nerve can cause carpal tunnel syndrome. This can include:

• swelling of tendons or other tissues within the carpal tunnel
• repetitive up-and-down bending of the tendons in the wrist and hand
• overuse of the hand and wrist tendons in jobs such as assembly line work and those that involve operating power tools and using electric knives for meat packing
• having another pinched nerve in your arm or spine
• having a medical condition such as diabetes, an overactive or under-active thyroid gland or rheumatoid arthritis
• bone spurs from or fractures of the bones under the tunnel
• having a family history of carpal tunnel syndrome
• hormone-related influences such as taking birth-control pills or being pregnant or menopausal
• smoking
• obesity
• excessive alcohol use
• trauma.

Excessive computer use has been implicated in the development of carpal tunnel syndrome but has not been proven to be a cause. Carpal tunnel is more common in women than in men.

SYMPTOMS AND SIGNS

• You may notice one or more of these symptoms: pain, numbness, burning and/or an electric shock feeling in your thumb, index finger, middle finger, and/or the palm beneath them.
• The abnormal feelings can be in one finger or multiple fingers.
• Pain and numbness can extend up the forearm to the elbow and sometimes to your upper arm.
• Symptoms, especially pain, frequently occur at night or are worse then.
• You may notice weakness when you grip things or you may start dropping things.
• You may have poor control of your fingers.
• Shaking your hand can sometimes decrease your symptoms briefly.
• Carpal tunnel symptoms happen right away after a wrist injury that causes a broken or displaced wrist bone. Otherwise, carpal tunnel syndrome is rarely an emergency.

WHEN TO CALL YOUR DOCTOR

Call your doctor right away if you have fallen and/or injured your wrist and:

• You have swelling, pain and/or numbness in your wrist or hand.
• You have problems moving your wrist properly.
• You hear crunching or grinding in your wrist.
• Your skin is pale and/or your hand feels cold.
• Your wrist looks deformed.

Call your doctor during regular office hours if:

• Your symptoms have lasted a long time (weeks to months) and are not relieved with home treatment such as using a wrist splint, wrist stretching exercises and taking anti-inflammatory medicines such as ibuprofen or naproxen. Permanent nerve damage can happen after long-term symptoms.
• Your symptoms, such as weakness, are getting worse or you start dropping things.
• You have symptoms such as numbness, tingling, pain or weakness in your arm or neck.

SELF-CARE AT HOME

• Take brief breaks during activities and sports that make your symptoms worse.
• Avoid using your affected hand too much and use your good hand as much as possible until you are getting better.
• Try holding things differently with your affected hand and avoid bending it down at the wrist for long periods.
• You may take ibuprofen (Advil® or Motrin®). (See the label for dose and risks.) Take it every six hours for swelling and inflammation.
• Get a neutral-position (slight bend) wrist splint (Figure 2) and use it while you are sleeping for four to six weeks to rest your median nerve and forearm tendons. If you do not have improvement in this time, see your doctor. Make sure the splint is not too tight.

Figure 2.

• You may also use the splint while doing things that make your carpal tunnel symptoms worse, but take it off to avoid stiffness when resting the wrist or when you are not actively using your wrist and hand.
• Place an ice pack or cold pack over the palm and wrist three times daily for 20 minutes at a time. Hold the pack in place with plastic wrap or an elastic wrap. You may want to place a thin washcloth between the ice pack or cold pack and your skin to minimize risk of frostbite.
• Studies show that doing yoga may help reduce symptoms of carpal tunnel syndrome. Stretching and strengthening exercises may help, but this is unproven.